The present invention, hereafter referred to as CPA, generally relates to the field of flying machines. More particularly, the present invention is related to rotary wing and fixed wing aircraft incorporating multiple wings attached to multiple rotors and a fuselage of teardrop shape.
Contemporary rotary wing aircraft and co-planar multi-rotor, multi-copter aircraft alike such as the typical well known co-planar quad-copter suffer nonlinear inefficiencies during both hover and non-hover horizontal flight conditions. In the specific case of co-planar multi-copter type aircraft, much inefficiency results from the use of small diameter fixed pitch rotors. In the general case of rotary wing aircraft, much inefficiency is incurred as a result of rotor induced turbulence and lift dissymmetry below and above the best rate of climb velocities respectively. During hover and horizontal flight conditions, co-planar multi-copters mitigate the induced roll effect due to lift dissymmetry with pairs of complimentary counter rotating rotors while the mono-rotor helicopter makes use of dynamic pitch control of the main rotor and torque control with a tail rotor. The counter rotating dual-rotor helicopter resolves lift dissymmetry in a similar manner as the co-planar multi-copter. Due to the low cost simplicity of small diameter fixed pitch rotors used in the co-planar multi-copter, overall rotor efficiency is impaired relative to the traditional large diameter helicopter rotor, with peak efficiency occurring near a single RPM.
Traditional rotary wing aircraft in general suffer from common high aerodynamic drag inefficiencies incurred during the lifting of high mass payloads at high horizontal air velocities. When such capability is required the designer of a heavy lifting helicopter must resort to expensive large diameter rotors and a similarly expensive and complicated, high drag rotor hub. Helicopter rotor lift is a function of rotor diameter, rotor blade number and radial velocity and thus there exist significant physical limitations involved in the design and production of an optimized rotary wing. In general aviation, the task of lifting high mass payloads are left to the much more suitable airplane.
Propeller driven fixed-wing aircraft mitigate rotary wing inefficiencies incurred at high horizontal air velocities and enable the lifting of high mass payloads by overcoming the lower induced drag incurred in moving a comparatively lower velocity, low wing-loading, high lift generating, low drag coefficient airfoil in the direction of aircraft motion. Together with a reduced power output propulsion system, the combination results in an aircraft with much diminished overall induced drag and therefore higher fuel efficiency.